Toy-sized quadrotors flying in formation

Researchers from GRASP Lab at the University of Pennsylvania developed software to allow toy-sized nano quadrotors to fly in tight, precise and eerie formation. Gmoke sez, "William Gibson dreams of a mass of these things comprising a flying skyscraper. I imagine them as surveillance and policing drones ready to stop the OWS action or Arab Spring before it can start."

A Swarm of Nano Quadrotors

(Thanks, Gmoke!)